As will be apparent from the above-mentioned patents, copending applications and the literature cited in the files therein, it is known to provide receptacles or containers for storage and transportation of nuclear materials, such as nuclear fuel elements, which may be withdrawn from a nuclear reactor core during the changing of a fuel, the container being designed such that it absorbs at least most of the emissions from the radioactive materials therein.
Such containers can be fabricated from cast iron and especially nodular or spherolitic cast iron or from cast steel and generally employ a shielding cover which has a plug portion fitting into a socket portion of the receptacle to minimize the escape of radiation from the interior of the container through the cover or through a joint between the cover and the container. This joint may be stepped and provided with seals.
The container generally is provided with a receiving chamber or compartment adapted to accommodate a plurality of nuclear fuel elements and the compartment can also be provided with a basket with nests, pockets or the like adapted to receive the respective fuel elements and serving to enable the fuel elements to be inserted into the compartment.
The bottom of the container is also generally relatively thick to prevent escape of radiation therethrough and may be formed in one piece or unitarily with the container into which the shielding cover is inserted. Other covers may also be applied for sealing and safety for redundancy purposes.
Such containers have been used for the storage of nuclear fuel elements as described, for example, in the publication Brennelementzwischenlagerung in Transportbehaltern--Fuel Element Temporary Storage in Transport Containers--of Preussen Electra dated February 1980. In this system, the fuel is not disassembled from the cans but rather is introduced in the form of fuel elements in the receiving shafts of the insert basket and is introduced with the latter into the compartment of the container. A given radiation shielding transport and storage container can only receive a certain number of the fuel elements and thus the number of fuel rods, i.e. the fuel bodies of these elements, which can be accommodated is likewise limited. In general, with cast iron or cast steel containers of the aforedescribed type, which have been used industrially, only sixteen irradiated fuel elements could be accommodated.